Re: Distant Gamma Ray Burster Nailed

Eugene Leitl (
Mon, 19 May 1997 22:17:58 +0200 (MET DST)

On Mon, 19 May 1997, Carl Feynman wrote:
> like the antimatter fountain. Since they vary over time scales as short as
> a millisecond, they can't be bigger than a light-millisecond across, i.e.
> 3000 km. I just did a back of the envelope calculation (well, in my head,
> actually) and determined that to get all the gamma rays from a burst into a
> volume that small, they would have to be compressed to the density of lead.
> Cool, huh? ^^^^^^^^^^^^^^^^^^^^

!!!!!????? Gamma at the density of lead? Now this is so wildly ridiculous,
it fails even to send a shiver down my spine.

Which processes can be _that_ energetic? Even if we assume colliding
neutron stars, travelling at their usual kinetical + gravitational
potential energy, and assume a high conversion efficiency (several
10%) to gamma, intuitively this doesn't suffice. I don't have
Carl's envelopes at the house, could anyone give some ballpark figures
on energetics of such events?

If a hole eats a pulsar in one fell gulp, how much energy is released
then? And why does my every darn sentence seem to end with a question
mark, today?

Since we are at the holes, and evaporating primeval singularties should
give a fair gamma flash (how fast? did somebody record the GBR spectral
changes)? before winking out, can one look out of them? (But these should
be very rapid, and extremely faint, being observable just in low lightyear